Inertia operated flare



July 9, 1968 R. H. WELDON ETAL 3,391,640

INERTIA OPERATED FLARE Filed July 7, 1966 2 Sheets-Sheet 1 July 9, 1968 R w o ET AL 3,391,640

INERTIA OPERATED FLARE Filed July 7, 1966 2 Sheets-Sheet 2 o o o United States Patent Ofice 3,391,649 Patented July 9, 1968 3,391,640 INERTIA OPERATED FLARE Robert H. Weldon, Elizabeth North, South Australia, and

lan L. Thompson, Elizabeth Park, South Australia, Australia, assignors to The Commonwealth of Australia, the Secretary, Department of Supply, Melbourne, Victoria, Australia Filed July 7, 1966, Ser. No. 563,575 Claims priority, application Australia, July 9, 1965, 61,283/65 7 Claims. (Cl. 10287) ABSTRACT OF THE DISCLOSURE An inertia operated flare having a flare body containing a charge and an ignition fuse at the rear of said body to ignite the charge. A component compartment is formed in the body at the front thereof and contains an energizing mechanism which is electrically connected to the fuse via sockets at the front of the said body. A nose cone is connected to the body but is ositioned forward of the body to leave a space therebetween in which are visible one of a number of pairs of interchangeable function controlling plugs which can be inserted into the sockets to adapt the flare for a safe transit condition, an armed condition or a test condition.

This invention relates to an inertia operated flare.

Flares used in conjunction with rocket firings require to be carried by the rockets and fired at the appropriate time such as when the acceleration reaches a predetermined value.

Problems associated with this type of flare are to attain simplicity of construction with ready facilities for testing and arming and also with ease of attachment to the rocket with which it is to be associated.

An object of this invention is to provide an improved flare which will be self-contained for independent attachment and operation and which will be simple to test and arm.

A further object is to allow ready testing to be effected, as well as to render the unit safe for transit, and to arm it.

A further object is to so construct the unit that an operator can at any time readily ascertain whether the unit is adjusted for transit or is armed.

A further object is to avoid the use of ground firing supply cables such as are required by'all conventional flares. These trailing cables have been known to cause damage to missiles by fouling projecting parts of the missile.

The inertia operated flare according to this invention comprises a flare body to contain a charge, an ignition fuse at the rear of the body to ignite the charge, a component compartment at the front of the body housing energizing mechanism, sockets at the front of the body electrically connected to the energizing mechanism and the fuse, and a nose cone connected to the body but positioned forward of the body, and interchangeable function controlling plugs to engage the sockets whereby the flare can be adapted for a required function, such for instance as for testing the circuits, for arming it, or for rendering it safe for transport.

According to one form of the invention the flare comprises a flare body containing the charge, which flare body is provided with a fusible end closure supporting the igniting fuse and which flare body has at its forward end a compartment which houses the battery whereby the fuse is initiated and an inertia-energized switch for controlling ignition, the forward end of the compartment containing a pair of sockets which are wired to the battery and the inertia-energized switch and which are adapted to receive control plugs Which are interchangeable with further control plugs so that when one set of plugs is in position, the flare is armed and ready to be fired under influence of the inertia-energized switch, and when other plugs are in position the flare is safe for transit, test plugs being insertable to allow the components to be checked, a removable nose cone holding the arming and transit plugs in place.

While the actual construction of the invention can be considerably varied, an embodiment will now be described but it is to be clear that the invention need not necessarily be limited to this, the scope of the invention being defined in the claims forming part of this specification.

In the drawings:

FIG. 1 is a side elevation of the flare,

FIG. 2 is a longitudinal section through the flare,

FIG. 3 is an end elevation,

FIG. 4 is a view of the electrical connections of the plugs to the functional parts, and

FIG. 5 is a schematic circuit diagram showing how the various functions may be initiated.

The flare body 1 consists of a tubular member having a component compartment 2 at the front end adapted to receive a battery 3 and an inertia-energized switch 4 as well as sockets 5 and 6 for control plugs 7 and 8. The body 1 contains a divisional wall 9 near the front end of the body which separates the charge-holding part 10 of the body from the component compartment 2. A forwardly projecting stem 11 is attached to wall 9 and the stem 11 is threaded at its forward end to engage a threaded socket 12 in the forward part 13 of the nose cone to hold it in position, this forward part in turn holding the rear part 14 of the nose cone in place. The rear section of the nose cone bears against the plugs 7 and 8 when they are in position to hold them firmly in place, but there is a gap 15 between the rear part 14 of the nose cone and the front of the flare body 1 through which the plugs 7 and 8 can be clearly seen.

Within the flare body 1, near its rear end, is a fusible membrane or wall 16 which seals the rear of the flare body so that the charge can be held in the space 19 between the forward Wall 9 and this rear wall 16, but the fusible wall 16 has in it a member 17 which carries the fuse 18 so that the charge can be ignite-d when this fuse is actuated.

The battery 3 can be of any standard design and fits into a section of the front component compartment 2, as does also the inertia-energized switch 4 which will be of the type in which the circuit is closed to energize the fuse when the necessary acceleration has been reached.

Just forwardly of the battery 3 and inertia-energized switch 4 are the sockets 5 and 6 previously referred to which are adapted to receive the control plugs 7 and 8, the sockets being wired to the battery 3 and inertia switch 4 as well as to the fuse 18 as shown in FIG. 4, the plugs 7 and 8 being arranged to engage these sockets and to change the circuits according to whether the flare is to be deenergized for transit or is to be armed for use, and also a plug is provided with leads for test apparatus, the circuits of the plugs being shown particularly in FIG. 5.

Referring now particularly to FIGS. 4 and 5, it will be noted that the battery 3 is connected to the contacts 21 and 22 of the socket 5, while the contacts 23 and 24 are connected respectively to the switch 4 and the contact 25 of the socket 6, the switch 4 being connected to the contacts 26 and 27 respectively of the socket 6. The contacts 28 and 29 of the socket 6 are connected by the shielded leads 30 and 31 to connectors 32 and 33 which couple to plugs 34 and 35 which in turn conmeet with the fuse 18.

The plugs 7 and 8 shown in the circuit diagram of FIG. 5 show the arming circuits, while 36 and 37 represent the unarmed or transit phase plugs.

The plug 39 is a test plug which has a series of leads 40 which can be taken to test instruments when such a plug is placed into either the socket 5 or the socket 6. The purpose of the lead 26 is to allow testing of the switch when the testing plug 39 is inserted. the leads from the contacts 26 and 27 then allowing bridging of the switch shown between these leads.

From the foregoing it will be realized that it is convenient to supply three sets of plugs, namely the pairs 7 and 8, the pairs 36 and 37 and the single test plug 39. The plugs 7 and 8 carry the wiring which will place all operative members into the circuit so as to form the arming plugs, which plugs will be painted in a distinctive color, preferably red. or will otherwise be distinctive to ensure that they indicate the armed state of. The flare.

the transit plugs 36 and 37 of course are blanks so that no circuit can be made when these are in position, these again being painted in a distinctive color. such as green or otherwise identified so that the required safety is ensured. The test plug is so arranged that when it is inserted the various members to be tested are connected into external test means.

By positioning the sockets 5 and 6 at the front of the flare body 1 itself and placing the plugs 7 and 8. or the plugs 36 and 37, into them and then positioning the nose cone 13-14 to hold the plugs in place. it will be realized that the gap 15 left between the rear race of the nose cone and the front face of the flare body 1 will allow the plugs to be readily seen. thus assuring that at all times by simply observing the color or identification on the plugs an operator can tell whether the unit is set for transit or is armed and ready for tiring.

The flare body can be attached to the rocket or the like by any convenient means, but forms a completely self-contained unit which can at that stage be readily tested because the nose cone can be unscrewed to release the plugs, or the plugs can be changed from transit to arm.

What we claim is:

1. An inertia operated flare comprising a tlare body having front and rear ends, a charge in said body, an nition fuse at the rear of said body to ignite said arge, a component compartment in the front of said body, an energizing mechanism in said component compartment, socket means in the front part of the said body, a nose cone adapted for being mounted on the trout of said body, electrical connections between said energizing mechanism and said fuse, means for removably securing the nose cone to the body, and interchangeable i'unction controlling plugs engageable in said socket means, time to establish a safe transit condition, a second to establish an armed condition, and a third to establish a testing condition.

it. An inertia operated flare according to claim 1 Wherein the nose cone engages said plugs When the latter are engaged in said socket means to hold said plugs in said socket means.

113. An inertia operated flare according to claim 1 wherein said nose cone has a rear face which is-spaced forwardly of the front end of the flare body when secured thereon to provide a space between said nose cone and hare body through which said function controlling plugs are visible.

4. An inertia operated flare according to claim 1 wherein said energizing mechanism comprises a battery and tin inertia switch in said compartment, the electrical connections between said energizing mechanism and said Ii'use extending externally of said body.

:5. An inertia operated flare according to claim 1, wherein said body comprises a fusible rear Wall carrying said ignition t'use.

t5. An inertia operated flare according to claim 5, wherein said function controlling plugs are arranged in respective pairs.

7. An inertia operated flare according to claim 6, wherein the third of the interchangeable function controlling plugs has leads adapted to be connected to external test apparatus.

Ilileferences Cited LJNITED STATES PATENTS .llll, 642,80l lit/1953 Gleason 10270.2 i1..il29.596 M1958 Loedding 10287 ROBERT F. STAHL, Primary Examiner. 

